Sulfonated cyclobutane compounds



Uted Smtes 3,005,014 SULFONATED CYCLOBUTANE COMPOUNDS James Herbert Werntz, Wilmington, Del., assignor to E. I. du Pont de Nemonrs and Company, Wilmington, DeL, a corporation of Delaware No Drawing. Filed Mar. 18, 1958, Ser. No. 722,137 18 Claims. (Cl. 260-464) This invention relates to sulfonated organic compounds. More particularly, it relates to sulfonated cyclic compounds that are capable of improving the atfinity of polyester fibers for basic dyes.

Polyester fibers, .e.g., fibers of polyethylene terephthalate, have various properties which make them valuable in many commercial applications. However, they do not possess as high afiin-ities for basic dyes as is desired in some cases. to obtain a novel and useful class of cyclobutanes; A further object is to prepare modifiers for polyester fibers that are capable of improving the dye affinity of such fibers for basic dyes.

The products of this invention are cyclobutanes containing (a) a sulf(HO S-) or sulfo-lower alkyl(HO S-- lower alkyl) group or a salt of either of these groups, and (b) at least one carboxyl (COOH) group or groups hydrolyzable thereto. The groups hydrolyzable to carboxyl include COOR, CONHR, COOM, and CN, wherein R is a monovalent hydrocarbon radical, R is H or R, and M is an ammonium radical, a substituted ammonium radical or a metal atom, i.e., cyano, carbamyl, N-hydrocarbylcarbamyl, hydrocarbyloxycarbonyl, metal car-boxylate, ammonium carboxylate and substituted ammonium carboxylate groups. Preferred because of the ready availability of the starting materials necessary for their. preparation are those cyclobutanes bearing the (a) and (b) groups respectively on two non-adjacent nuclear carbons,

any other substituents on such carbons being alkyl (preferably 16 carbon alkyl, i.e., lower alkyl) and at most one of the remaining nuclear carbons being substituted and. that mono-substituted with a second (b) group in which case'the (b) groups taken together-may be the divalent (a) is Ho,s MO3S, HO S-lower alkyl-, or MO38- lower alkyl- (b) is COOI-I, --COOR, COOM, -CONHR' or ,CN (x) is H or (b) (x) and (b) together is (y) is n or lower alkyl I RR and M are defined as above.

One object of the present invention is atent The sulfonated cyclobutanecarboxylic acids and derivatives hydrolyz able thereto which form the products of this invention are prepared by reacting a water-soluble bisulfite with a 3-methylenecyclobutanecarboxylic acid, a 3- alkyl-Z-cyclobutene-1,2-dicarboxylic acid, or==a derivative of either of these that is'hydrolyzable to the respective acid. This reaction is conveniently carried 'out'by contacting the cyclobutane or cyclobutene reactant with a water-soluble bisulfite, e.g., ammonium or sodium bisulfite, in a polar solvent, e.g., water or an alcohol, at .a temperature between 0 C. and 175 C., preferably until the products are dissolved in the reaction mixture. Mixtures of the bisulfites can be used.

The proportions ofreactants used are not critical; however, it is preferred that an excess (i.e., above stoichiometric amounts) of bisulfite, e.g., a 50'l00%. excess of bisulfite, be employed. Likewise, the concentration of the bisulfite in the solvent is not critical, concentrations of bisulfites ranging up to 65% being operable. However, it is preferred to use bisulfite concentrations ranging up While temperatures between 0 and 175 C. are satisfactory, higher temperatures can be used if desired but they do not give any better results. The reaction is preferably carried out at temperatures between 25 C. and the reflux temperature of the reaction mixture, as this can be carried out at atmospheric pressure. Temperatures above the boiling point of thereaction mixture are operable and can be used if desired provided a closed reaction system which is capable of withstanding the super-atmospheric pressures developed at these higher temperatures is employed. l

Any polar solvent can be used in the process. Water, methanol, ethanol and mixtures of water with these alcohols, are preferred since they are most economical and give excellent results. V I

While it is not necessary to carry out the reaction in an inert atmosphere, itis preferred to do so to avoid peroxide formation during the reaction, particularly when azo catalysts are being used. Nitrogen or other inert gas, e.g., helium, is satisfactory for blanketing the reaction mixture. I V i V The reaction between the bisulfite and the methylenecyclobutaneor cyclobutenecarboxylic, acid takes place in the absence of a catalyst. However, it is often desirable to use a catalyst, especially when reactants having double bonds of low reactivity are employed. Suitable catalysts include organic peroxides, e.g., benzoyl peroxide, tertiary butyl hydroperoxide, inorganic Lperoxy compounds, e.g., ammonium p'ersulfate, azo compounds, e.g., a,a'-azodiisobutyronitrile, and ultraviolet light. Catalysts are ordinarily used in amounts up to'about 15% by weight of the cyclic compound.

When operating in water'solutions, a pH range between 2 and 8.0 is used. There is substantially less oxidation of the bisulfite at pH 6 than at pH 3. Under certain conditions, the reaction becomes more acidic as it proceeds and it is frequently desirable to add a buffering agent in order to maintain the pH at a constant 'value. The preferred pH range is between 3 and 6. I

The time required to complete the reaction, between the bisulfite and the methylenecyclobutane-, or cyclobutenecarboxylic' acid is dependent on such factors as the reaction temperature and 'the relative reactivity of the doublebonds in the unsaturated reactants.v Times ranging from 4 hours at reflux temperature of an aqueous Patented Oct. 17, 1961 Q reaction mixture to days at room temperature are common. It is customary, but not necessary, to continue the reaction until all the products are dissolved in the reaction mixture.

The invention is illustrated in further detail in the following examples in which the proportions of ingredients are expressed in parts by Weight unless otherwise noted.

EXAMPLE I Ammonium salt of 3-sulfome thylcyclobutanecarbonitrile Sixty-seven parts of a 45% aqueous solution of ammonium bisulfite (containing30 parts of ammonium bisulfite), 233 parts of deoxygenated water, 2.7 parts of a 70% solution of djisopropylbenzene hydroperoxide, and 18.4 parts of 3-methylenecyclobutanecarbonitrile are charged into a glass reaction vessel and stirred under an atmosphere of nitrogen. At the start of the reaction the acidity of the reaction mixture is at pH 5.9. After stirring for 24 hours the pH rises to 6.5, and after 48 hours rises to pH 7.8. The pH is then adjusted by the addition of dilute sulfuric acid to 6.7, but it rises again in 30 minutes to a pH of 7.4. The reaction mixture is stirred under nitrogen for an additional 3 days. At the end of this time there is still an unreacted oil layer amounting to 2.5 parts. Three hundred parts of the aqueous layer is poured into approximately 1200 parts of absolute ethyl alcohol and the unreacted ammonium bisulfite which precipitates is filtered off. The filtrate is concentrated to about one-tenth of its volume, diluted with 2 volumes of ethyl alcohol, and evaporated at room temperature. The resulting crystalline product is dissolved in about 240 parts of hot absolute ethyl alcohol and is then filtered. The filtrate is concentrated to about one-third of its volume and 18.6 parts of cream-colored solid ammonium salt of 3-sulfomethyleneeyclobutanecarbonitrile separates.

Analysis.,-Calcd for C H N SQ N, 14.6%; S, 16.7%. Found: N, 14.3%; S, 17.2%.

EXAMPLE II Sodium salt of 3-sulfomethylcycl0butanecarbonitrile A mixture of 18.4 parts of B-methylenecyclobutanecarbonitn'le, 31.2 parts of sodium bisulfite, 270 parts of water and 1.84 parts of t-butyl peroxide, having a pH of 4.5, is stirred under nitrogen for 24 hours. After stirring for 18 hours, all of the oil layer is dissolved. The sodium salt of 3-sulfomethylcyclobutanecarbonitrile obtained in this way is a white solid which is soluble in Water.

EXAMPLE HI 3-sulf0methylcyclobutanecarboxylic acid and its disodium salt A reaction vessel is charged with the crude reaction mixture containing the sodium salt of 3-sulfomethylcyclobutanecarbonitrile made as described in Example H, and 40 parts of sodium hydroxide is dissolved in the mixture. The reaction mixture is stirred at reflux temperature for 30 hours. After cooling, the reaction mixture is extracted once with diethyl ether. The aqueous layer containing the disodium salt of 3-sulfomethylcyclobutanecarboxylic acid is filtered and made strongly acid with gaseous hydrogen chloride. The sodium chloride which forms is filtered OE and the filtrate is evaporated to about one-third of its original volume. An equal volume of dioxane is added to the filtrate which is then saturated with gaseous hydrogen chloride, and the sodiurn chloride which forms is filtered 01f. The filtrate is concentrated to about one-half of its volume and then diluted with an equal volume of methyl alcohol. The solution is saturated with gaseous hydrogen chloride and a small amount of sodium chloride which forms is filtered off. The filtrate is evaporated under reduced pressure and finally heated on a steam bath at 5 mm. pressure. The residue amounting to 38 parts, is a brown, viscous, water-soluble oil. This is crude 3-sulfomethylcyclobutanecarboxylic acid.

Analysis.Calcd for C H SO S, 16.5%; NE, 97. Found: S, 20.5%; NE, 104.

This crude acid is suitable for use Without purification in various applications, as illustrated below.

A 1% aqueous solution of crystal violet is heated on a steam bath, and a small strip of fabric made of polyethylene terephthalate fibers is placed, in it for. 15 minutes. The fabric is removed from the dye bath, washed with cold water until the washings are colorless and then air-dried. The fabric is dyed a light blue. A strip of polyethylene terephthalate fabric is dyed 15 minutes in an aqueous solution containing 1% crystal violet and 5% 3-sulfomethylcyclobutanecarboxylic acid heated on a steam bath. The dyed fabric is washed with cold water until the washings are colorless and then airdried. In this case the fabric is dyed a dark blue. This shows the effectiveness of 3-sulfomethylcyclobutanecarboxylic acid as a dyeing assistant. In similar tests, 3-sulfomethylcyclobutanecarboxylic acid is shown to be a dyeing assistant for basis dyes such as Rowes Colour Index No. 512, N,N-tetraethyl-3,7-diaminophenoxazine, and those of the type of Astrazone pink FG (Lubs Chemistry of Snythetic Dyes and Pigments, A.C.S. Monograph 127, p. 250).

EXAMPLE IV Dimethyl 3-sulf0-3-methylcyclobutane-LZ-dicarboxylate (sodium salt) A mixture of 18.4 parts of dimethyl 3-methyl-2-cyclobutene-1,2-dicarboxylate, 15.6 parts of sodium bisulfite, 270 parts of deoxygenated water, and 1.84 parts of t-butyl peroxide is stirred overnight at room temperature. The reaction mixture is exposed to ultraviolet light for 8 hours and then stirred overnight. All of the ester is now reacted, as evidenced by its complete solution in the reaction mixture. The reaction mixture is concentrated to about one-third of its original volume by heating on a steam bath, and is then diluted with an equal volume of methanol to precipitate 4.9 parts of unreacted sodium bisulfite. The filtrate is evaporated on a steam bath under a vacuum of about 25 mm. pressure. There is obtained 24 parts of colorless, amorphous solid readily soluble in water which is the sodium salt of dimethyl 3-sulfo-3- methylcyclobutane-1,2-dicarboxylate.

EXAMPLE V 3-sulfomethylcyclobutane LZ-dicarboxylic acid, sodium salt, and triethyl ester A mixture of 27.6 parts (0.2 mole) of 3-methylene-l,2- cyclobutanedicarboxylic anhydride, 31.2 parts (0.3 mole) of sodium bisulfite and 50 parts of water is heated on a steam bath with stirring for 4 hours. The mixture is cooled in ice and saturated with dry hydrogen chloride, and then is diluted with ethyl alcohol to precipitate the sodium chloride which forms. The precipitated sodium chloride is filtered out and the filtrate is evaporated in vacuum at room temperature. The dilution with ethyl alcohol and saturation with hydrogen chloride are repeated. Sodium chloride which forms is again filtered out. The filtrate is concentrated under a vacuum of about 25 mm. pressure at room temperature. There is obtained a heavy oil that has a neutral equivalent of 205. (The theoretical neutral equivalent for 3-sulfomethylcyclobutane-1,2-dicarboxylic acid is 79.0.) This oil is evapo-' The total amount of product amounts to 44.6 parts, which corresponds to 69.4% of the theoretical yield.

EXAMPLE v1 3-sulfomethylcyclobutane 1,2 dicarboxylic acid'qnd sodium salt Example V is repeated with the same quantities of reactants and the same reaction conditions. The resultant aqueous solution of the sodium salt of 3-sulfomethylcyclobutane-1,2-dicarboxylic acid ispassed through a 1-inch by 20-inch column packed with the ion exchange resin sold under the trademark Amberlite IR-120. The column is then eluted with water and the eluate is concentrated to a small volume. When the volume of solution reaches approximately 100 parts, a small amount of solid separates. This solid is 3-sulfomethylcyclobutane- 1,2-dicarboxylic acid, having amelting point of 162l75 C. and it amounts to 5.9 parts, corresponding to a yield of 12.6%.

Analysis.-Calcd for C H O S; N.E., 79.0. Found: NE, 79.5.

The filtrate obtained after the removal of the above acid is evaporated to constant weight in a vacuum oven at 60 C. and -20 mm. pressure. These is thus obtained 40.1 parts (corresponding to an 84% yield) of crude 3- sulfomethylcyclobutane-l,2 dicarboxylic acid as a black oil that has a neutral equivalent of'92.5.

The examples above have illustrated the preparation of products included in this invention by reference to certain sulfonated cyclobutanecarboxylic acids, and derivatives hydrolyzable thereto. It is readily apparent that other cyclobutanes having (a) a sulfoor sulfoalkyl group, or a salt of these groups, and (b) at least one carboxyl group or group hydrolyzable thereto are within the scope of the invention. Thus, when the specific methylenecyclobutanecarboxylic acids and derivatives hydrolyzable thereto listed in Table I below are substituted for the specific methylenccyclobutanecarboxylic acids and derivatives thereof of Examples I, H, V and VI and reacted with aqueous bisulfites, and the reactiorrproducm wurkefi' upw irr tlresuiionated eyciobutmbcxyiic aeids with ammonia those examples, the specific sulfonated cyclobutaneca'r boxylic acids, and derivatives hydrolyzable thereto, listed in the second columnof Table I, are obtained. i

TABLE I.

Methylenecyclobutanecarbcxylic Acid React-ant Sulfonated Cyclobutanecarboxyllc Acid Products 1-Methyl-3-methylenecyclobutanecarboxylic acid.

l Methyl-B-methyleneeyclobutanecarboxamide/ Methyl 3-methylenecyclobutanecarboxylate.

3-Meghylenecyclobutanecarboxylic aei Dlethyl 3-methylenecye1obutane- 1,2'dicarboxylate.

1-Methyl-B-methylenecyclobutauecarbonitrile.

1 Methyl 3 sull'omethyleyclobu tanecarboxylic acid, and ammonium salt.

1 Methyl 3 sulfomethylcyclobu -tanecarboxamide, and sodium salt. Methyl 3-snliomethylcyclobutai1e carboxylate, and sodium salt.

8 Suliomethylcyclobutanecarbox ylic acid, and potassiumsalt. Diethyl 3-suliomethylcyclobutane- 1,2-dicarboxylate (sodium salt). 1 Methyl 3 sulfomethylcyclobu tanecarbonltrile.

.mannn n- 1- Alkyleyelobuteneearbo xyllc Acid Reactant .Sulionated flyclobutanecarboxylic Acid Products 3-Methyl-2-cyclobutene-1,2-dlcarboxylic acid.

3-Methyl-2-cyclobuteue-1,2-dlcarboxamide.

' hi tle l a= elebntene=l 2 dlear bo xanillde.

Disodium a-methyl-z eyelobutene- 1,2dicarboxylate.

3-h-Hexyl-2-cyclobutene-1,2-dicarboxylic acid.

3-Su1to-3-methylcyclobutane-l,2-

dglcarboxylic acid, and sodium 3 sulto -3 methyleyclobutane 1,2 dlcarboxamide, and ammonium dlcirboxanilide, and potassium s Trisodlum 3-sulio-3-methyl cyclobutane-1,2-dicarboxylate.

3:Sulio-3-n-hexyleyclobutane-1,2-

,dlcarboxylic acid, and sodium salt. Diethyl 3-sulio-3-isobutylcyclobu- Dlethyl 3-isobutyl-2 cyclobutene- 1,2-dicarboxylate. tane-LZ-dicarboxylate, sodium salt.

The methylenecyclobutanecarboxylic acids, and derivatives hydrolyzable thereto, used as starting materials in making the products of this invention can be prepared by heating at 150-250" C., in'the absence of a polymerization initiator, a mixture of an allene having at least one of the terminal carbon atoms of the allene group unsubstituted, and a substituted ethylene having a carboxyl group or group hydrolyzable thereto. This process is described in greater detail in U.S. application Serial No. 532,376, filed September 2, 1955, by H. N. Cripps, now U.S. Patent 2,914,541. v

- The 3-alkyl-2-cyclobutene-1,Z-dicarboxylic acids are prepared by treating 3-alkylidene-1,2-cyclobutanedicarboxylic anhydrides having at least one hydrogen atom on the carbon of the alkylidene group attached to the cyclo butane'ring with an aqueous alkali having a pH of more than 7.5 at ordinary or elevated temperatures, preferably at 70l20 C., followed by acidification of the reaction amines, e.g., methylamine, dimethylamine and triethauolamine, sodium, potassium and other metals, e.g., barium,

calcium, cobalt, lead, copper and iron. The salts of ammonia, amines, sodium and potassium can be prepared directly by reaction of the appropriate salts of methylenecyclobutaneor cyclobutene-carboxylic acids and a bisulfite, .while'the other salts, particularly those of polyvalent metals, can be prepared by simple metathesis between an aqueous solution of analkali metal salt of the sulionated cyclobutanecarboxylic acid and an aqueous solution of a salt of the appropriate polyvalent metal.

Likewise, the esters and amides of the sulfonated cyclobutaneearboxylic acids can be made directly as described previously or they can be made from the free acids by esterification or amidation reactions. Thus, esters of the sulfonated cyclobutanecarboxylic acids with alcohols and phenols, e.g., methanol, ethanol, butanol, phenol, etc. and amides of these acids with ammonia, methylamine, ,-diethylamine, etc. can be prepared by converting the acid to the 1 acid chloride by reaction with thionyl chloride and then reacting the acid chloride with the appropri} ate alcohol, phenol or amine.

The products of this invention are especially useful as dye assistants in the dyeing of polyester fibers and fabrics with basic dyes. They are also useful as tanning agents for leather, and the salts are surface-active agents. High 7 boiling esters and amides of the sulfonated cyclobutanecarboxylic acids of this invention arealso useful as plasticizers for polymeric materials,e.g cellulose esters and ethers.

I claim:

1. Cyclobutanes having the following structural formula H 1) H-( 3( )(b) wherein (a) is selected from the class consisting of sulfo, and sulfo-lower alkyl groups and salts thereof; (b) is carboxyl; (x) is selected from the class consisting of H and (b); (x) and (b) together may equal a II [I -o-o-owherein (a) is selected from the class consisting of sulfo and sulfo-lower alkyl groups, and salts thereof, (x) is 'selected from the class consisting of H and CN and (y) is selected from the class consisting of H and lower alk l.

3 Cyclobutanes having the following structural formula i t i H-CCCNH2 (v) (a) H wherein (a) is selected from the class consisting of sulfo and sulfo-lower alkyl groups, and salts thereof, (at) is selected from the class consisting of ll 11 and -CNH:

and (y) is selected from the class consisting of H and lower alkyl. I

4. Cyclobutanes having the following structural formula class consisting of H and lower allcyl.

5. Cyclobutanes having the following structural formula wherein (a) is selected from thev class consisting of sulfo and sulfo-lower alkyl groups, and salts thereof, (b) is hydrocarbyloxycarbonyl, (x) is selected from the class consisting of Hand (b) and (y)is selected from the class consisting of H and lower alkyl. 7

6. Cyclobutanes having the following structural formula wherein (a) is selected from the class consisting of suJfo and sulfo-lower alkyl groups, and salts thereof, (b) is metal carboxylate, (x) is selected from the class consisting of H and (b) and (y) is selected from the class consisting of H and lower alkyl. 7

7. Cyclobutanes having the following structural formula wherein (a) is selected from the class consisting of suite and sulfo lower alkyl groups, and salts thereof, (x), is selected from the class consisting of i HandCONH4 and (y) is selected from the class consisting of H and lower alkyl.

8. Cyclobutaues having the following structural formula wherein (a) is selected from the class consisting of sulfo and sulfo-lower alkyl groups, and salts thereof, (b) is selected from the class consisting of methylammonium carboxylate, dimethylammonium' carboxylate and triethanolammonium carboxylate, (x) is selected from the classconsisting of H and (b) and (y) is selected from the class consisting of H and lower alkyl.

9. A method of making sulfonated cyclic compounds which comprises contacting, in a polar solvent at a temperature of at least 0 C., a water-soluble bisulfite with a member of the group consisting of 3-rnethy-lenecyclobutanecarboxylic acids and 3-lower alkyl2-cyclobutene-' 1,2-dicarboxylic acids.

10. The process of claim 9 wherein the water-soluble bisulfite is sodium bisulfite.

1 1. The process of claim 9 wherein the water-soluble bisulfite is ammonium bisulfite.

12. A method of preparing sulfonatcd cyclobutanes which comprises contacting 3methylenecyclobutanecarbonitrile with a water-soluble bisulfite in a polar solvent at a temperature of at least 0 C.

13. A method of preparing sulfonated cyclobutanes which comprises contacting dimethyl 3-methyl-2-cyclo- 

1. CYCLOBUTANES HAVING THE FORMULA 